求URL重写正则表达式

求URL重写正则表达式

希望可以把http://www.163.com/enterpriseColumn.aspx?userId=aaaa 重写成 http://www.163.com/aaaa
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<configSections>
<section name="urlrewritingnet" restartOnExternalChanges="true" requirePermission="false" type="UrlRewritingNet.Configuration.UrlRewriteSection, UrlRewritingNet.UrlRewriter"/>
</configSections>
<urlrewritingnet rewriteOnlyVirtualUrls="true" contextItemsPrefix="QueryString" defaultPage="default.aspx" defaultProvider="RegEx" xmlns="http://www.urlrewriting.net/schemas/config/2006/07">
<rewrites>
<add name="Rewrite" virtualUrl="^/jmx/(.*)" rewriteUrlParameter="ExcludeFromClientQueryString" destinationUrl="enterpriseColumn.aspx?userId=$2" rewrite="Domain" ignoreCase="true"/>
</rewrites>
</urlrewritingnet>